1. Field of the Invention
This invention relates to an abrasive member useful, for instance, as an abrasive tape or a cleaning tape to be used for polishing or cleaning of a magnetic head for a magnetic recording and reproducing apparatus or to be used for polishing, burnishing, texturing, or cleaning of various materials, particularly magnetic recording media. This invention particularly relates to an abrasive material particularly useful for an abrasive tape to be used for rough polishing, finish polishing of a magnetic head for video tape recorders or audio decks and a cleaning tape to be used for cleaning of such magnetic head.
2. Description of the Prior Art
Video or audio magnetic heads are required to have very smooth tape sliding surfaces and to be free of any foreign substance, such as dust. Therefore, in general, during the process for making the magnetic head, the magnetic head is located at a predetermined position after being roughly polished, and two reels are located with the magnetic head intervening therebetween. In this state, an abrasive tape is moved between the two reels in order to polish the tape sliding surface of the magnetic head. Also, an abrasive tape is incorporated in a cassette and moved therein in order to remove any foreign substance from the tape sliding surface of the magnetic head. In general, the abrasive tape comprises a nonmagnetic substrate and an abrasive layer, which is overlaid on the substrate and primarily comprises fine abrasive grains and a binder or fine abrasive grains, ferromagnetic fine powder and a binder. Since the abrasive tape is flexible, it can snugly fit to and move along the curved surface of the tape sliding surface of the magnetic head and accordingly is capable of accurately polishing and smoothing the tape sliding surface of the magnetic head and reliably removing any foreign substance from the tape sliding surface of the magnetic head.
As disclosed, for instance, in Japanese Unexamined Patent Publication Nos. 62(1987)-92205 and 63(1988)-47069 and Japanese Patent Publication No. 4(1992)-22283, it has been known to add various lubricants such as silicone oil to the abrasive layer in order to improve fitness of the abrasive tape to the magnetic head and lubricity therebetween.
With the progress of high-density recording, various magnetic heads, such as thin-film heads, amorphous heads, laminated heads, MIG heads, and MR heads, have been proposed and have widely been used. It has been difficult to polish a magnetic head having a small width to a desired shape and to a smooth finish without changing the properties, and to remove foreign substances from a magnetic head without decreasing the effective depth.